Science – Page 50 – a sibilant intake of breath

Climate change and winter

During the last few days, I have had a depressing number of people approach me quasi-triumphantly, pointing to either the CRU emails or the first winter snowfall as evidence that climate change is nothing to worry about.

Both comments are worrisome, given that we are in the midst of negotiations at Copenhagen that will play a significant role in determining whether we keep temperature rise under 2°C or not. The CRU emails already have a post of their own, but I thought I would say a couple of things about winter.

The latter argument – about the snow – is especially absurd. Climate change is about a shifting distribution of temperatures. There will always be extremes of hot and cold, it’s just that the former are becoming more frequent relative to the latter. That said, I recall reading about a study that found that most Canadians cannot explain why there are seasons at all, with a plurality offering the theory that is has to do with the distance between the Earth and the sun. Of course, our winter is summer in the southern hemisphere, which shows that this hypothesis cannot be valid. Winters are the consequence of the fact that the Earth rotates on an axis that is presently tilted 23.44° off from the direction of our orbit. That makes the length of days variable, and changes how the distribution of temperatures across the globe plays out. That level of tilt varies across geological time due to tidal forces. When the tilt is greater, the variation between the seasons is alo larger; when the tilt is lesser, the weather towards the poles remains more consistent year-round. The level of tilt has an affect on processes like glaciation.

This will continue to happen essentially forever, regardless of how much warming we experience. The distant polar regions will always experience months of darkness, and will thus always be colder than the equator during those spans. Indeed, this is a nice demonstration of what a massive amount of energy the sun adds to the Earth system. None of this disproves the fact that greenhouse gasses being added to the atmosphere warm the planetary system overall.

The two queries also highlight some potentially important psychological issues. People on both sides of the argument are sometimes overly quick to grab at any piece of evidence that seems to support what they already believe. In his book, Greg Craven goes on at some length about the importance of this ‘confirmation bias.’ Such sloppy reasoning is one reason why the climate change debate is so flawed. Hard as it can be to do so, we need to question data and sources of information even when they seem to confirm our existing beliefs – just as we must take into consideration sources and data that seem to contradict what we hold to be true. That doesn’t mean, however, that we should remain paralyzed forever, unable to take action due to uncertainty. We take precautionary action on the basis of uncertain threats all the time. A risk management approach to climate change is one where the preponderance of evidence is sufficient to drive preventative action.

Above and beyond that, I think the fact that people cheerily point to a snowfall to argue that the planet isn’t in danger shows that they don’t yet seriously appreciate how dangerous climate change could be. The fact that it is still often treated as a half-joking matter bodes ill for our ability to put our society on a course where the largest risks of catastrophic or runaway climate change can be avoided.

What’s the Worst That Could Happen?

Written by a high school science teacher, Greg Craven’s What’s the Worst That Could Happen? A Rational Response to the Climate Change Debate is a worthwhile and unusual addition to the catalogue of books on climate change. Craven’s chosen task is not to determine whether climate scientists are right in their projections of what human activity is and will do to the climate; rather, he is trying to prepare readers to make the best choice, given the uncertainty that will always exist.

This is the same basic message he popularized in a series of viral videos, the first and last of which are especially worth watching:

I do have one slight quibble with both. Craven’s decision grid suggests that we will eventually be able to look back and know if we made the right choice. I don’t think that’s true. If we take aggressive action and stop climate change, we may never know with certainty just how bad it would have been if we had ignored it. No matter how sophisticated they become, simulations can never give us total certainty, and we don’t have another planet with which to run an experiment. Similarly, if we take no action and climate change proves catastrophic, we will never know for sure what level of action would have been sufficient to stop it – or whether doing so was still possible at any particular point in time.

Craven’s approach is based around heuristics: examining the ways in which people make decisions, taking into consideration pitfalls like confirmation bias, and then developing an approach to make an intelligent choice. In this case, it involves developing a way to roughly rank the credibility of sources, look at who is saying what, and complete a decision grid that shows the consequences of climate change either being or not being a major problem and humanity either taking or not taking major action. His own conclusion is that taking action unnecessarily isn’t likely to be exceptionally economically damaging, and can be considered a prudent course for ensuring that the worst does not happen.

On the question of why action has not yet been taken, Craven focuses primarily on human psychology. We respond to threats that are immediate, visible, and have a hostile agent behind them. Since climate change is none of these things, it doesn’t trigger strong responses in us. Cognitive factors also help explain why people are so confused about the state of climate science, though individual failings in information assessment are accompanied by the failure of the media to pass along good information effectively.

Craven concludes that raising political will is the key action that needs to be taken, and that cutting individual emissions is of very secondary importance. Like many others, he draws on the analogy of WWII to show what the United States is capable of achieving when it has the determination.

Some readers may find the book’s informal style and fill-in-the-blanks exercises a bit annoying, or feel that they trivialize the issues at hand. That being said, Craven has produced a very accessible book that recasts the climate change debate in a valuable new way: evaluating what choice to make, under uncertainty, rather than trying to determine authoritatively who is right. For those wishing to grapple with the practical question of what ought to be done about climate change, this book is well worth reading.

Gore on CCS

In Our Choice, Al Gore adopts a position on carbon capture and storage (CCS) that is rather similar to my own. Namely, that there are big uncertainties, and little reason to expect CCS to emerge as a silver bullet that lets us mostly carry on with business as usual. Gore does, however, argue that the safety issues associated with CCS are not terribly significant.

One statistic he quotes seems especially notable:

If all the CO2 now being vented into the atmosphere by U.S. coal electricity plants were captured and converted into its liquid form, the volume would be equivalent to 30 million barrels of oil per day – three times the volumes of all the oil imported by the United States each day. If the CO2 were then transported by pipeline to repositories, as proposed, the amount (by volume) would be one third of that of all natural gas now being transported in pipelines throughout the U.S. (p. 136 paperback)

Think about the infrastructure associated with moving those quantities of fossil fuels, and you can better appreciate that CCS won’t be cheap and easy, even if it does eventually prove workable.

One surprising thing is that Gore doesn’t seem to mention how CCS could be used in combination with biomass-fuelled power plants to actually reduce the amount of CO2 in the air

The Globe and Mail on fossil fuels and the oil sands

In an editorial that is reasonably good overall, The Globe and Mail is nonetheless too quick to assume that the oil sands are good for Canada: “A vital resource, the oil sands, are an economic advantage to Canada, indeed to North America as a whole. Sixty per cent of our natural gas is exported, and Canada is the U.S.’s largest source of crude oil. The fruits of emissions here are often enjoyed elsewhere” and that fossil fuels “remain vital assets that will serve as reliable sources of energy for the foreseeable future.” They also claim that: “Products from the oil sands are necessary and desirable.”

I have argued before that, when all the associated costs are taken into consideration, the oil sands may be net destroyers of human wealth and welfare. The most important of these costs is the degree to which extracting, processing, and burning fuels produced from the oil sands increases the risk of catastrophic climate change. If we use a very high but possible estimate for how sensitive the climate system is to greenhouse gas emissions (8°C of warming for each doubling of CO2 concentrations), burning the 1.7 trillion barrels of oil estimated to exist in the oil sands would alone be sufficient to increase mean global temperatures by 2°C. Even using the probable estimates of 3.5 – 4.5°C of warming, the oil sands represent a contribution to total cumulative human emissions that is seriously out of proportion to Canada’s population, or even the population of those who ultimately consume the fuels produced.

The oil sands represent the last gasp of a fossil fuel powered economy. Either because of hydrocarbon depletion or because of climatic concerns, we are inevitably going to have to give up fossil fuels anyhow. Given what we now know about the climate system and the potential impact humanity could have on it, we should be working on developing zero-carbon sources of energy – not on extracting the oil that is the hardest to reach, or which requires the most processing to be turned into usable fuels or products. Rather than picking at the bones of the fossil fuel carcass, we should be seeking out new forms of sustenance.

The Globe and Mail has a history of assuming that oil sands development is good for Canada. In fact, the best thing we could do for future generations of Canadians (and others around the world) is to leave that dangerous carbon in the ground, while pursuing the development of sustainable forms of energy.

What if you’re wrong?

Whatever your position on climate change policy, this question is a good one to ask. It drives you to do two important things: consider what it would take to change your mind, and consider the risks associated with making the wrong choice.

I would change my position on what action we should take in response to climate change if any of the following was adequately demonstrated:

The Earth’s climate is not changing.
Greenhouse gas emissions are not the cause of warming.
Warming will not be dangerous.

Exactly what level of evidence would be required is difficult to pre-judge, but the definitive rebuttal of any of those positions would be sufficient to prompt a major change in the policies I would advocate.

On the question of risks, there are two major kinds of error we could make: over- and under-reacting. If we over-react to climate change, we would sacrifice wealth and other opportunities in order to cut out emissions, achieving no good purpose. At the very worst, we would seriously damage the global economy for an indefinite span of time, and delay the emergence of many people from extreme poverty. If we under-react, the very worst outcome would be the undermining of the capability of the planet to support human life. This is clearly a much worse outcome, though it is not an easy task to determine how probable it is, relative to the ‘overreact and go broke’ possibility. Clearly, I think that the risks of climate change as it is now understood justify much more action than we have taken to date.

Another thing to bear in mind is that there are co-benefits to shifting the energy basis of our society from fossil fuels to zero-carbon and renewable options. In his response to the Munk Debate, Tyler Hamilton lays out a few: “I mean, even in the unlikely event that climate change science shows us we overreacted, is it such a bad thing that we also acted to reduce air pollution, mercury emissions, the use of water in thermal power plants, and the other environmental footprints caused by our addiction to fossil fuels. That’s a pretty nice consolation prize.” In a situation where we took aggressive action, we would also be better protected from the distinct but related challenge of peak oil. Fossil fuels are inevitably going to run out anyhow, so the real cost here is of making the transition away from them earlier than we otherwise would. Climate change or not, a fossil fuel based economy simply cannot keep going forever.

Ultimately, the choice we make on climate change policies is a matter of risk management. Being able to hedge against a potentially catastrophic risk, and secure co-benefits, while simultaneously running some risk of overreacting seems much more prudent and sensible than doing the opposite.

Military assessments of climate change

In his scrupulously evenhanded book What’s the Worst That Could Happen? A Rational Response to the Climate Change Debate, Greg Craven makes reference to four different assessments of climate change conducted by organizations with a link to the American military. All conclude that climate change is a serious problem, and that actions must be taken to mitigate it.

The first is the 2008 National Intelligence Assessment, drafted by 16 U.S. intelligence agencies including the CIA, FBI, and NSA. While the report itself is classified, the chairman said that climate change could disrupt US access to raw materials, create millions of refugees, and cause water shortages and damage from melting permafrost.

Another is a 2003 Pentagon study: An Abrupt Climate Change Scenario and Its Implications for United States National Security: Imagining the Unthinkable. It considers a worst-case but plausible scenario, and concludes that abrupt climate change could destabilize the geopolitical environment:

In short, while the US itself will be relatively better off and with more adaptive capacity, it will find itself in a world where Europe will be struggling internally, large number so [sic] refugees washing up on its shores and Asia in serious crisis over food and water. Disruption and conflict will be endemic features of life.

It also argues that “with inadequate preparation, the result [of abrupt climate change] could be a significant drop in the human carrying capacity of the Earth’s environment.”

The third report is from the Center for Naval Analyses. Their “blue-ribbon panel of retired admirals and generals from the Army, Navy, Air Force, and Marines” produced the report National Security and the Threat of Climate Change. It calls climate change “potentially devastating” and advises that the risks to national security will “almost certainly” get worse if mitigation action is delayed. It also stresses how we don’t require 100% certainty about the precise seriousness of a threat before it starts making sense to address it.

The last report was drafted by two national security think tanks: the Center for Strategic and International Studies and the Center for a New American Security. Their 2007 report is titled: The Age of Consequences: The Foreign Policy and National Security Implications of Global Climate Change. Their team included the head of the National Academy of Sciences, one Nobel laureate economist, a former CIA director, a former presidential chief of staff, climatologists, and others. They concluded that current projections from climate models are “too conservative” and that “at higher ranges of the [warming] spectrum, chaos awaits.” The authors conclude that an effective response would have to occur in less than a decade “in order to have any chance” of preventing irreversible disaster.”

The only fair conclusion that it seems possible to reach about these reports is that they have been ignored. If American policy-makers and members of the general public accepted these conclusions – and interpreted them with the seriousness accorded to matters of national security – we would not be seeing so much doddering around before meaningful action is taken. While the military does have an incentive to scare people, since doing so likely increases their funding, Craven is probably right to claim that the overall bias of these organizations is towards economic strength rather than environmental protection. That, and the calibre of the individuals associated with these reports, seems to provide good reason for taking them seriously.

Note that the issue of climate change and security has been discussed here previously.

Black carbon and climate change

[Image removed at the request of a subject (2019-10-01)]

Al Gore’s latest book – Our Choice: A Plan to Solve the Climate Crisis – includes a fair bit of discussion of black carbon, a human pollutant that causes global warming, but not in the same way carbon dioxide (CO2) does. Greenhouse gasses like CO2 prevent long-wave infrared radiation from leaving the Earth into space. Black carbon, by contrast, warms the planet by absorbing a lot of short-wave radiation from the sun. In essence, it has a very low albedo.

Some other pertinent things to know about black carbon:

The largest source is biomass combustion – such as burning forests and grasslands to clear them for agriculture.
The areas where this is happening most are Brazil, Indonesia, and Central Africa.
Black carbon settling in the Arctic is a major cause of warming there: possibly responsible for 1°C of the 2.5°C of warming already observed there.
Black carbon is also a major threat to Himalayan glaciers, which in turn provide the source water for rivers of critical human importance, such as the Ganges.
Black carbon is washed out of the atmosphere by rain, and only has a lifetime of a few weeks. If we stopped emitting it, its contribution to climate change would cease quickly.

The last of those is very encouraging. Unlike CO2, which remains in the atmosphere for a very long span of time, black carbon is something we could tackle on a short timescale, by mandating things like filters on diesel engines and the cleaner burning of coal and biomass.

As mentioned before, recent research has also highlighted the importance of non-CO2 greenhouse gasses. Anything that allows us to take more rapid and effective action to halt climate change is welcome news. Also, it requires a lot less political will to install better filters on diesel engines than it does to curb activities that are critically linked to greenhouse gas emissions.

Obama’s 17% climate mitigation target

Writing at Boing Boing, Saul Griffith has come up with a good analysis of President Barack Obama’s recently pledged climate change mitigation target of “17 percent below 2005 levels by 2020 and 83 percent by 2050:”

As you’ll note, a 17% reduction over 2005 levels means only a 0.3% reduction over 1990 levels.

What you’ll also see is that Obama is making a commitment to emit 59 Gigatons from the US alone from 2010-2020, and a further 88 Gigatons from 2020-2050, for a total of 147 Gigatons of CO2. This is 22.7% of the 650 Gigaton limit implied by Meinshausen. This helps to see why it’s hard to get an agreement in Copenhagen. In order to avoid “dangerous levels of climate change” the US is committing to reduce its output to “only” 22.7% of global emissions, despite having only 4.5% of the global population. The other point to note is that even these reductions don’t satisfy the “emissions go to zero” aspect of this CO2 budget, as the US would still be emitting a gigaton of CO2 per year in 2050 under this plan.

As discussed here before, crafting a global emissions pathway to keep warming below 2°C is very challenging, particularly because of how countries with high per-capita emissions need to begin deep cuts very quickly. There is still an enormous gap between what is physically necessary to prevent dangerous climate change and the commitments that governments and politicians are willing to make.

That said, Obama’s target can legitimately be seen as part of an iterative process: a recognition that America cannot continue to emit greenhouse gasses in an unrestrained way. Eventually, however, the proposed cuts are going to need to get much deeper, or we are all going to have to start bracing for the changed world that more than 2°C of climate change would produce.

Climate Cover-Up

James Hoggan’s Climate Cover-Up: The Crusade to Deny Global Warming is a valuable exposé of the efforts that have been made by self-interested actors to prevent political action on climate change, by manipulating the public debate and confusing people about the strength of the science. Written by a Canadian public relations professional, and written with a focus on actors and events in Canada, Hoggan’s book examines how the media has been involved in the debate, how companies have worked to create false grassroots campaigns (‘astroturfing’), the role played by think tanks, the use of lawsuits to intimidate and silence critics, the ‘echo chamber’ effect wherein false claims are endlessly repeated by sympathetic sources, and more. Hoggan makes a convincing case that status quo actors – particularly petrochemical firms – have been working for decades to keep the public confused, and keep legislators inactive.

Hoggan provides both logical and documentary evidence to back up his claims – pointing out things like how most of the scientists that actively deny the consensus view of climate change are being funded as advocates, not as scientists:

The Intermountain Rural Electric Association isn’t paying Pat Michaels to go back into his lab and do research helping the world to a better understanding of how human activities are affecting the climate. The coal-fired utility owners are paying him to “stand up against the alarmists and bring a balance to the discussion.”

Hoggan provides many specific examples of malfeasance, and argues that the public relations personal directing the campaign against action on climate change are often indifferent to whether the claims they are making are true or false. They are tested for how well they affect public opinion, not how well they represent the reality of the situation.

Hoggan does sometimes present information in a misleading way. For instance, he compares the risk of climate change with the risk of car and house insurance, and says that: “in both cases the risk of disaster is significantly less than the greater than 90 percent certainty that scientists ascribe to the climate crisis.” He is referring to how the IPCC’s Fourth Assessment Report concluded that: “Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic GHG concentrations.” and defined ‘very likely’ as cases where “expert judgment and statistical analysis of a body of evidence” support an assessed probability of over 90%. The IPCC was saying that there is a scientific consensus that there is a 90% chance that the unequivocal warming that has been observed has anthropogenic causes, not that the “risk of disaster” is 90%. The question of how serious the consequences of warming will be is distinct from the question of what is causing warming. Another odd error is one sentence written as though the consulting company McKinsey was a person: “When McKinsey talks about a carbon revolution, he strikes the right tone.”

That said, Climate Cover-Up succeeds in its key purpose: revealing that not everyone is engaging in the climate debate in an honest or ethical manner. The scientific consensus that climate change is real and risky is exceedingly strong, and yet the public and policy-makers have been very effectively confused and encouraged to delay action. By revealing the extent to which the debate has been manipulated, Hoggan’s book will hopefully contribute to the eventual improvement of public understanding of climate change, and the development of a will to act sufficiently strong to sort out the problem before the worst potential consequences become inevitable. Hoggan also continues that effort through DeSmogBlog – a site he created to provide ongoing updates on climate change misinformation campaigns.

[Update: 13 October 2010] Another good book on the same topic is Naomi Oreskes’ Merchants of Doubt: How a Handful of Scientists Obscured the Truth on Issues from Tobacco Smoke to Global Warming.

Getting to carbon neutrality

Responding to an unusually poor article, written by Lorrie Goldstein and printed in the Toronto Sun, I wrote that: “If you want high human welfare and prosperity for decades and generations ahead, dealing with climate change is not optional. The longer Canada waits to begin the process of going carbon-neutral, the more costly and painful that process will be.”

The above graphic, included in the recent Copenhagen Diagnosis, illustrates this situation nicely. The graphic shows three different pathways, each of which would give humanity a 75% chance of limiting warming to 2°C – a target that has been widely endorsed by governments, including those of the UK and EU. In a scenario where global emissions peak in 2011, they would only need to fall to about 5 gigatonnes by 2050, a reduction rate of 3.7% per year. Waiting just four more years, and having them peak in 2015, increases that to 5.3% per year. In the scenario with the 2015 peak, humanity as a whole needs to be carbon neutral before 2050, in order to provide the 75% certainty of avoiding more than 2°C of warming. Waiting until 2020 means that emissions need to fall by 9% per year afterwards, with carbon neutrality reached around 2040.

Bear in mind that these are global pathways. Under a contraction and convergence approach, where countries cut emissions while simultaneously becoming more equal in terms of per capita emissions, Canada would need to cut even faster. This illustrates firstly how wrongheaded it is to hope for a few more years of a hydrocarbon boom before we start the process of adjustment. It also illustrates the urgency of getting an effective global agreement in place soon. This isn’t an issue on which we can simply doddle for a decade. If we don’t want to see our children living in a transformed world, humanity needs to act fast and on a massive scale.

On a personal level, this may also bring some clarity to the many discussions we’ve had here about carbon ethics. If we individually want to mirror what the world as a whole needs to do, we should be planning to have our personal emissions peak virtually instantly, and fall every year thereafter. People who are my age should be thinking seriously about the possibility of living carbon-neutral lives by the time they face retirement – and about what accomplishing that would require.